Water-soluble disazo dyestuffs and a process for their manufacture



Patented Apr. 23, 1 946 WATER-SOLUBLE DISAZO DYESTUFFS AND A PROCESS FOR THEIR Guido Schetty, Basel, Switzerland, assl'gnor to gy A. G., Basel, Switzerland, a Swiss No Drawing. Application December 20, 1943, Se-

i198; No. 515,027. In Switzerland December 23,

Claims. (Cl. 260-190) It has been found that water-soluble disazo dyestufls dyeing animal fibres in blue shades are obtained by combining a diazotised amino-aryl sulfonic acid-aryl ester sulfonic acid with o-naphthylamine, further diazotising the obtained amino azo dyestufi and coupling the diazo compound with a 1-arylamino-naphthalene-8-suifonic acid. As initial components there come into question for example l-aminobenzene-s-sulfonic acid phenyl ester-m'-sulfonic acid, 4- or 6-methyll-aminobenzene 3 sulfonic acid '2'- methylphenyl ester-a:'-sulfonic acid, 6- or 4-chloro-laminobenzene-il-sulfonic acid 2'- methyl -(or -2'-methoxy-) phenyl ester-:r'-sulfonic acid, 6- or 4-methoxy 1 aminobenzene-ll-sulfonic acid 2'- methyyphenyl-ester :r'- sulfonic acid.

1-aryl-aminonaphthalene-8-sulfonic acid, the

new dyestufis obtainable according to the present invention show a better levelling power, somewhat better light-fastness, moreover, mostly purer shades and often a better evening color besides equally good fastness properties in .the moist state.

the so-obtained amino azo dyestufi is suspended in 400 parts of water and clearly dissolved by means of sodium carbonate. After addition of a solution of 7.6 parts of sodium nitrite this solution is cooled down to 0-5 G., the same is treated with 50 parts of concentrated hydrochloric acid. After completion of the diazotation the brown, dimcultly soluble diazo compound is isolated and, while stirring, added to a solution'consisting of 32.1 parts of the sodium salt of l-phenylaminonaphthalene-8-sulfonic acid, 17 parts of crystallised sodium acetate and 5 parts of acetic acid in 400 parts of water. After some hours the dyestufi' formation is complete. ()n heating to 70 C. and neutralising by means of sodium carbonate the dyestufi precipitates out in form of a dark bronzy powder which is hot filtered off, washed with a warm diluted solution of common salt and finally dried. The dyestuff dyes wool from a neutral or slightly acid bath in even full, blue shades of excellent iastness properties to fulling and to sea-water and of very good light-fastness. If in the above example the starting component is replaced by l-aminobenzene-3-sulfonic acid- 2-methylphenylester-:r'-sulfonic acid, a dyestufi" is obtained which constitutes a dark bronzy powder dissolving in water with a blue coloration and dyeing wool in blue shades oi. excellent fastness properties. Instead of l-phenylaminonaphthalene-8-sulfonic acid, l-p-tolylaminonaphthalene-B-sulfonic acid may be used.

Similar dyestufls are obtained by using l-amino-benzene-ii-sulfonic acid phenylestera:'- su1fonic acid, 1-aminobenzene-3-sulfonic acid- 3 2'-'methoxyor -2-ethoxyor -2'-propoxy henyl- The following examples, without being limi-Y- tative, illustrate the present invention. The parts are by weight.

Example 1 35.7 parts of G-methyl-l-aminobenzene-3- sulfonic acid-2'-methylphenylester-m-sulfonic acid are neutral dissolved in 100 parts of warm water by means of 5.4 parts of anhydrous sodium carbonate, then treated with a solution of 6.9 parts of sodium nitrite and allowed to run under cooling into a solution of 29 parts of concentrated hydrochloric acid in 50 parts of water. The diazo compound, which partly has precipitated in a powdery form, is coupled in the usual manner with 14.3 parts of o-naphthylamine, then ester-x'-sulfonic acid, 4-methyl-1-aminobenzene- 3-sulfonic acid-2'-methylphenylester-a:-sulfonic acid 'or l-aminobenzene-ii-sulfonic acid-1'- or -2'-naphthylester-a:'-sulfonic acid and the like instead of G-methyl-l-aminobenzene-3-sulfonic acid-2'-methylphenylester-x-sulfonic acid.

Example 2 thin-liquid suspension of the said amino azo dyestufl treated with 7.6 parts of sodium nitrite are added 50 parts of concentrated hydrochloric acid. Then the brown diazo compound thus completely precipitated is filtered by suction after some hours, again suspended with 200 parts of cold water, coupled with 32.1 parts of the sodium salt of l-phenylaminonaphthalene-8- sulfonic acid in the manner described in Example l and the finished diazo dyestui! is isolated. After drying it constitutes a dark bronzy powder dyeing wool from a neutral or slightly acid bath in very even, bloomy, blue shades of excellent i'astness properties to fulling and to sea-water and of a very good light-fastness.

If in this Example the d-chloro-l-aminobenzene-ii-sulfonic acid-2'-methylphenylestera:'-sulfonic acid is replaced by fi-chloro-l-aminobenzene 3-sulfonic acid-2'-methylphenylestercf-sulfonic acid, a dyestuil' is obtained which is a dark, bronzy powder dissolving in water with a blue coloration and dyeing wool in blue shades of very good fastness properties.

What I claim is:

1. Process for the manufacture of soluble disazo dyestuffs, which comprises coupling a diazotised compound of the general formula Y QH:

wherein Y stands for a member of the group consisting of H, Cl and CH3, with c-naphthylamine, diazotising the amino azo dyestuil and coupling the diazo compound with l-phenylaminonaphthalene-8-sulionic acid.

3. Process for the manufacture of a soluble disazo dyestuil, which comprises coupling the diazotised compound of the formula CH: 0L0? on! with a-naphthylamine, diazotising the amino azo dyestuil! and coupling the diazo compound with l-phenylaminonaphthalene-ii-sulfonic acid.

4. Process for the manuiactunof a soluble disazo dyestuil', which comprises coupling the diazotised compound of the formula sons with e-naphthylamine, diazotising the .amino azo dyestufl and coupling the diazo compound with l-phenylaminonaphthalene-B-sulfonic acid.

5. Process for the manufacture of a soluble disazo dyestufi, which comprises coupling the diazotised compound of the formula 80,.0 oal with a-naphthylamine, diazotising the amino azo dyestuil and coupling the diazo compound with l-phenylaminonaphthalene-B-sulfonic acid.

6. The dyestufis of the general formula N=N N=N Nix-Q OIH wherein Y stands for a member of the group consisting of H, Cl and CH3, being dark powders,

dissolving in water with a blue coloration and dyeing wool in blue shades of excellent lightbeing a. dark powder, dissolving in water with a fastness. blue coloration and dyeing wool in blue shades 8. The dyestuff of the formula of excellent llght-fastness.

QN=N N=N NH Z02 $01K I OH: H055 being a, dark .powcler, dissolving in water with a. 10. The dyestuif of the formula 802 S OIH -CH| l I Hols blue coloration and dyeing wool in blue shades of being a. dark powder, dissolving in water with a.

excellent light-fastness. blue coloration and dyeing wool in blue shades 9. The dyestuff of the formula of excellent light-iastness.

N= N =N NH O; SOaH CH: HO:

GUIDO SCHETTY. 

